Study on Cooling performance of rapid cooling system based on Vacuum spray flash evaporation

Abstract This study investigates the cooling performance of a passive cooling system for electric motor cooling applications. The metal-based phase change materials are used for cooling the motor and preventing its temperature rise. As compared to oil-based phase change materials, these materials have a higher melting point and thermal conductivity. The flow field and transient heat conduction are simulated using the finite volume method. The accuracy of numerical values obtained from the simulation of the phase change materials is validated. The sensitivity of the numerical results to the number of computational elements and time step value is assessed. The main goal of adopting the phase change material based passive cooling system is to maintain the operational motor temperature in the allowed range for applications with high and repetitive peak power demands such as electric vehicles by using phase change materials in cooling channels twisted around the motor. Moreover, this study investigates the effect of the phase change material container arrangement on the cooling performance of the under study cooling system.

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Cooling Performance Enhancement of Air-Cooled Condensers by Guiding Air Flow

Energies ◽

10.3390/en12183503 ◽

2019 ◽

Vol 12 (18) ◽

pp. 3503

Author(s):

Huang ◽

Chen ◽

Yang ◽

Du ◽

Yang

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Heat Dissipation ◽

Performance Enhancement ◽

Cooling System ◽

Wind Effects ◽

Cooling Performance ◽

Air Cooled Condensers ◽

Arc Shape

Adverse wind effects on the thermo-flow performances of air-cooled condensers (ACCs) can be effectively restrained by wind-proof devices, such as air deflectors. Based on a 2 × 300 MW coal-fired power generation unit, two types (plane and arc) of air deflectors were installed beneath the peripheral fans to improve the ACC’s cooling performance. With and without air deflectors, the air velocity, temperature, and pressure fields near the ACCs were simulated and analyzed in various windy conditions. The total air mass flow rate and unit back pressure were calculated and compared. The results show that, with the guidance of deflectors, reverse flows are obviously suppressed in the upwind condenser cells under windy conditions, which is conducive to an increased mass flow rate and heat dissipation and, subsequently, introduces a favorable thermo-flow performance of the cooling system. When the wind speed increases, the leading flow effect of the air deflectors improves, and improvements in the ACC’s performance in the wind directions of 45° and –45° are more satisfactory. However, hot plume recirculation may impede performance when the wind direction is 0°. For all cases, air deflectors in an arc shape are recommended to restrain the disadvantageous wind effects.

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Cooling performance of a pump-driven two phase cooling system for free cooling in data centers

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2015.11.002 ◽

2016 ◽

Vol 95 ◽

pp. 143-149 ◽

Cited By ~ 29

Author(s):

Yuezheng Ma ◽

Guoyuan Ma ◽

Shuang Zhang ◽

Feng Zhou

Keyword(s):

Data Centers ◽

Cooling System ◽

Two Phase ◽

Cooling Performance ◽

Free Cooling ◽

Two Phase Cooling

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A Novel Electronics Cooling System Using Water Heat Pipes Under Freezing Conditions

2003 International Electronic Packaging Technical Conference and Exhibition, Volume 2 ◽

10.1115/ipack2003-35098 ◽

2003 ◽

Author(s):

Osamu Suzuki ◽

Atsuo Nishihara

Keyword(s):

Prediction Model ◽

Thermal Resistance ◽

Ambient Temperature ◽

Cooling System ◽

Electronics Cooling ◽

Heat Pipes ◽

System Model ◽

Cooling Performance ◽

Temperature Range ◽

Metal Block

A novel electronics cooling system that uses water heat pipes under an ambient temperature range from −30°C to 40°C has been developed. The system consists of several water heat pipes, air-cooled fins, and a metal block. The heat pipes are separated into two groups according to the thermal resistance of their fins. One set of heat pipes, which have fins with higher thermal resistance, operates under an ambient temperature range from −30°C to 40°C. The other set, which have lower resistance, operates from 0°C to 40°C. A prediction model based on the frozen-startup limitation of a single heat pipe was first devised and experimentally verified. Then, a prediction model for the whole-system was formulated according to the former model. The whole-system model was used to design a prototype cooling system, and it was confirmed that the prototype has a suitable cooling performance for an environmentally friendly electronics cooling system.

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Numerical investigation of air cooling system for a densely packed battery to enhance the cooling performance through cell arrangement strategy

International Journal of Energy Research ◽

10.1002/er.7571 ◽

2021 ◽

Author(s):

Patcharin Saechan ◽

Isares Dhuchakallaya

Keyword(s):

Numerical Investigation ◽

Cooling System ◽

Air Cooling ◽

Cooling Performance ◽

Cell Arrangement ◽

Air Cooling System

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Influence of a Leaking Gap Downstream of the Injection Holes on Film Cooling Performance

Volume 4: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/96-gt-175 ◽

1996 ◽

Cited By ~ 4

Author(s):

Y. Yu ◽

M. K. Chyu

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Transfer Coefficient ◽

Film Cooling ◽

Cooling System ◽

Convective Transport ◽

Hole Injection ◽

Thermochromic Liquid Crystal ◽

Cooling Performance ◽

Temperature Problem

This study investigated a practical but never exploited issue concerning the influence of flow leakage through a gap downstream on the film cooling performance with a row of discrete-hole injection. A heat transfer system as such can be categorized as either a three-temperature or a four-temperature problem, depending on the direction of leakage through the gap. To fully characterize a three-temperature based film-cooling system requires knowledge of both local film effectiveness and heat transfer coefficient. A second film effectiveness is necessary for characterizing a four-temperature problem. All these variables can be experimentally determined, based on the transient method of thermochromic liquid crystal imaging. Although the overall convective transport in the region is expected to be dependent on the blowing ratios of the coolants, the mass flow ratio of the two injectants, and the geometry, the current results indicated that the extent of flow injection or extraction through the gap has significant effects on the film effectiveness and less on the heat transfer coefficient which is primarily dominated by the geometric disturbance of gap presence.

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A Parametric Investigation of Vane Showerhead Film Cooling by PSP Technique

Volume 5B: Heat Transfer ◽

10.1115/gt2019-90019 ◽

2019 ◽

Author(s):

H. Abdeh ◽

G. Barigozzi ◽

S. Ravelli ◽

S. Rouina

Keyword(s):

Turbulence Intensity ◽

Film Cooling ◽

Cooling System ◽

Density Ratio ◽

Leading Edge ◽

Intensity Level ◽

Cooling Performance ◽

Blowing Ratio ◽

Cylindrical Holes ◽

Exit Mach Number

Abstract In this study a parametric analysis of the thermal performance of a nozzle vane cascade with a showerhead cooling system made of four rows of cylindrical holes was carried out by using the Pressure Sensitive Paint (PSP) technique. Coolant-to-mainstream blowing ratio (BR), density ratio (DR), main flow isentropic exit Mach number (Ma2is) and turbulence intensity level (Tu1) were the considered parameters. The cascade was tested in an atmospheric wind tunnel at Ma2is values ranging from 0.2 to 0.6, with an inlet turbulence intensity level of 1.6% and 9%, at variable injection conditions of BR = 2.0, 3.0, 4.0. Moreover, the influence of DR on the leading edge film cooling performance was investigated: testing was carried out at DR = 1.0, using nitrogen as foreign gas, and DR = 1.5, with carbon dioxide serving as coolant. In the near-hole region, higher BR and Ma2is resulted in higher effectiveness, while higher mainstream turbulence intensity reduced the thermal coverage in between the rows of holes, whatever the BR. Further downstream along the vane pressure side, the effectiveness was negatively affected by rising BR, but positively influenced by lowering the mainstream turbulence intensity. Moreover, a decrease in DR caused a reduction in the film cooling performance, whose extent depends on the injection condition.

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